How do I tell if my HVAC air filter needs changing?

A woman sneezing next to a ductless unit

A clean HVAC filter is essential to ensure your heating and cooling systems run correctly. The purpose of your filter is to keep the air in your home purified, free from dust, allergens, and pollutants, and to ensure proper airflow through the system and ductwork. If you don’t change your filter frequently enough, it can cause a plethora of issues for your health and the well-being of your HVAC equipment. To know exactly how often you need to change the filter, check the type of filter you have and consult with an HVAC professional. Many filters will need to be changed every three months, but it’s essential to assess the exact time frame because factors such as pets or respiratory concerns should be taken into account and may require more frequent attention.

When your filter is clogged with dirt and debris, it is no longer effective and can cause damage to your HVAC system. So how do you know when it’s time to change your HVAC filter? Here are some clues to look out for:

When your filter is clogged with dirt and debris, it is no longer effective and can cause damage to your HVAC system.

Filter color

The easiest way to tell if it’s time to change your filter is to take a look at its color. Most filters are white; therefore, if your filter is white, it doesn’t need to be changed. If the color is light gray, again, you can wait a bit longer to change the filter. If the filter is a little darker, pay attention to the signs listed below to see if your filter needs changing. A dark gray color means your HVAC system is functioning well but needs a new filter. If your filter is brown or black, consult a trained HVAC technician to ensure there are not any malfunctions causing such a dark color.

Reduced airflow

If you notice your heating or air conditioning system is not producing as much air as it used to, it could be a sign that your filter is clogged. Reduced airflow can cause your HVAC system to work harder, increasing energy costs and potentially damaging your system over time. If you change your filter and you still notice reduced airflow, your ductwork may need to be cleaned as well.

If your energy bills are increasing without any apparent reason, your HVAC system may be working too hard to maintain your home's climate.

Increased energy bills

If your energy bills are going up without any apparent reason, there’s a chance that your HVAC system is working too hard to maintain your home’s climate. A clogged filter can cause the system to work harder to circulate air, leading to increased energy consumption and higher bills. By changing the filter regularly, you can keep energy costs down and extend the life of the HVAC system.

Dust and debris

If you clean your home on a regular basis but are still noticing that dust and debris are building up around your home quickly, it could indicate that the HVAC filter needs to be changed. When your filter is full of dust, debris, and pollutants, it can no longer filter out these particles. Consequentially, they are then pumped back through the system and can flow through the ductwork and into your home. When this happens, your ductwork will become dirty and may be damaged. Additionally, this issue will lead to poor indoor air quality and potential health problems for you and your family. Changing your filter more frequently is an easy way to help keep your home clean and free from allergens and pollutants.

Unpleasant odors

If you smell a funk coming from your ducts, this could be a sign that your HVAC filter needs to be changed. Especially in humid environments, a clogged filter can create mold and bacteria growth, leading to musty or disagreeable odors in your home. Mold is dangerous and can cause several health issues, so pay close attention to its development in and around your system. Changing the filter at the right time can aid in keeping your home smelling fresh and clean.

Changing your HVAC filter is integral to maintaining your heating, ventilation, and air conditioning systems. By checking for these signs, you can ensure that your filter is changed at the right time, helping to keep your home clean, healthy, and comfortable.

If your question isn’t answered here, contact the Pierce Refrigeration team, and one of our experts will guide you to finding your solution.

Need 24-7 emergency service? Looking for advice on improving your everyday air quality and comfort at home and at work? Contact the friendly staff at Pierce Refrigeration at 800-696-1088.


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